On the local server of html5-video is reproduced in all browsers, but on the fighting web server refuses to be reproduced
<video controls width="640" height="360" autoplay="true">
<source src="video.ogv" type="video/ogg" />
<source src="video.mp4" type="video/mp4" />
</video>
Use an HTTP monitor such as the one built into Firebug (on the ‘Net’ tab) to see what the response to the HTTP request for the video file is.
Possibly the production web server is returning the wrong Content-Type for .ogv and/or .mp4 files. (It should be video/ogg and video/mp4, respectively.) If so you would need to configure it to add the new MIME media types; how you do this depends on what server software you are using.